Quantizing the loss in the process of compression

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How is the loss quantized prior to compression before artifacts appear? Is there anyway to find out how much compression can the video be done to ensure that it is still acceptable?

-- Sandy Tay (taysandy.dynamics@stengg.com), January 04, 2001

Answers

Some blockiness is unavoidable as Mpeg 1 cannot cope with lots of changes between frames. So even on Pro VCD movie disks if there are explosions or lots of action in a scene it will get blocky. If the source you copy from is 'jumpy' or 'stutters' this will be encoded blockily as mpeg1 compression algorithams break down. Even small jumps in the screen that you ignore when watching the disk will cause major problems to compression.

ENSURE THAT THE PICTURE FROM THE CAMCORDER IS STEADY AND AVOID MANY CUTS OR PANNING. MPEG 1 DOES NOT LIKE DIFFERING FRAMES. IF YOU RECOGNIZE THIS FACT YOUR PICTURE QUALITY WILL IMPROVE.

Why not buy a pro. video cd movie and see what sort of quality you can expect to get - here are some legitimate Malaysian sources to buy from. Cut and paste URL into your browser.

http://www.d8a.co.uk/video-cds-vcd-shop-uk.htm

-- Wyze (hemail@ukfun.com), January 06, 2001.


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